Short term, lack of sleep scrambles our mental functioning. Long term, the health consequences can be dire. What’s stopping us from getting enough?

For many, adequate sleep is elusive because of sleep disorders, including varieties of insomnia. For others there are practical challenges – baby care or night shifts, for example. A new study focuses on another major, yet strangely overlooked, reason – bedtime procrastination. You want to go to bed early. You know you need to get to bed. And yet you stay up watching TV, playing video games or working late.

Floor Kroese and her colleagues surveyed over two thousand people (age range 16 to 93) in The Netherlands about their sleep habits and self-control. The participants also kept a seven-day sleep diary. All were free from medical sleep disorders or night shift jobs. Overall, the group averaged 7.2 hours sleep a night, but 17.5 per cent of them felt certain they didn’t get enough sleep in general, and over 50 per cent believed they didn’t get sufficient sleep on two nights or more a week.

Looking at the factors that were associated with insufficient sleep, demographics such as age and gender accounted for 8 per cent of the variation in sleep (being younger and female went hand in hand with less sleep), and external factors outside of one’s control accounted for an additional 4.6 per cent. But the headline result is that 12.7 per cent of variation in sleep was explained by self-confessed bedtime procrastination – choosing to engage in activities even though it was time for bed. Lack of self control in general was also associated with insufficient sleep, but this was at least partly explained by co-occurrence of low self-control and greater bedtime procrastination.

“It can be speculated,” the researchers said, “that people who have low self-regulation skills are more likely to keep watching the late night movie, or play yet another computer game despite knowing they might regret it the next morning when waking up tired.”

Kroese and her team are careful to say this is speculation because their methodology does not prove there is a causal role for low self control and bedtime procrastination. It’s possible – indeed likely – that lack of sleep adversely affects self control, thus increasing bedtime procrastination. Nonetheless, it makes sense that the causality runs in both directions and that lack of sleep is for many a self-regulation problem.

If so, the researchers point out that this self-regulation perspective puts lack of sleep “on par with other health behaviour problems such as getting too little exercise, or making unhealthy food choices.” This has implications not just for how we understand the problem, they explained, but also for highlighting potential interventions that could be borrowed from these other areas, such as the use of “if-then” plans. These rehearsed plans help overcome unhelpful habits by setting up new automatic routines or rules – such as, “if I’m feeling tired, then I will switch off the TV”.